Impact of neuromodulating drugs on the human gut microbiome
Research type
Research Study
Full title
Impact of neuromodulating drugs on the composition and metabolic function of the gut microbiota
IRAS ID
363390
Contact name
Maria de Fatima Cardoso Pereira
Contact email
Sponsor organisation
University of Southampton
Duration of Study in the UK
2 years, 11 months, 30 days
Research summary
The human gut is home to trillions of microorganisms that provide essential benefits to the human host, such as aiding digestion and supporting neurological function via the microbiome-gut-brain axis. The composition and function of the gut microbiome are influenced by external factors. It is now recognised that widely prescribed human pharmaceutical drugs are key modulators of the gut microbiome. Therefore, it is crucial to understand how drugs interact with gut microbes, as these interactions can significantly affect how well a treatment works, by disrupting the communication between the gut and the brain, or by preventing the drug from being absorbed properly.
Through lab experiments, we previously found that drugs affecting the brain (neuromodulatory drugs) can also affect the activity of gut bacteria in healthy people. Neuromodulating drugs such as antidepressants, are being prescribed at increasing rates worldwide. However, their effectiveness varies between individuals. Genetics accounts for some of this variability, but it cannot fully explain the differences between responders and non-responders. Based on this, we hypothesise that the therapeutic effects of these medications are modulated by people’s own gut microbiome.
Neuromodulating drugs are commonly prescribed to people with depression. To investigate how these medications and the microbiome interact, and whether the microbiome can influence their therapeutic effects through microbial metabolic processes, we will analyse the microbiome in stool samples from patients with anxiety and depression taking and not taking the medications of interest. Studying these patients is essential, as they are known to harbour distinct microbiome profiles associated with their conditions, which differ from those of healthy individuals. Ultimately, this research could open new avenues for optimising treatment outcomes.
We plan to recruit 62 adult patients diagnosed with major depressive disorder from Hampshire and Isle of Wight Healthcare NHS Foundation Trust over three years. Following informed consent, participants will provide one fresh stool sample (∼1 g each) during the study.REC name
London - West London & GTAC Research Ethics Committee
REC reference
26/PR/0494
Date of REC Opinion
13 May 2026
REC opinion
Further Information Favourable Opinion